In this section, we provide the results of some numerical experiments
illustrating the performance of \(\hat{f}_{n, V}^d\)  and
\(\hat{f}_{n, V}^{d, s}\)  and compare them with the performance of the
usual MARS estimator, which we will
write as \(\hat{f}_{\text{mars}}\) . The results for simulated data are
presented first, and those for real data follow next. We utilize the
R package \(\mathsf {Rmosek}\)  (based on interior point convex
optimization) to solve the problem
(REF ) (and
(REF )) and use the equation
(REF ) (and
(REF )) to construct our
estimator. For the usual MARS estimator \(\hat{f}_{\text{mars}}\) , we
use the R package \(\mathsf {earth}\)  based on [1]} and
[2]}.
